in reply to Win32::API: deciphering a returned pointer to a struct

  1. Always turn on double quotes before using Data::Dumper on data with possible unprintable data;
    otherwise, you cannot tell what your data really is: 
    local $Data::Dumper::Useqq = 1;

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  2. Ignore the keys typedef and buffer_recipients in the Dumper output. This will leave you with just the expected fields in DOMAIN_CONTROLLER_INFO, and an extra buffer field which contains the raw bytes of the structure.
  3. What happens if you declare the DsGetDcName API using the `prototype` style, instead of the older `parameter list` style you are using? Does that resolve the problem, or at least change the behavior? i.e. change: 
    my $DsGetDcName = Win32::API->new('Netapi32', 'DsGetDcName', 'PPSPNS',
+ 'N')
  or die Win32::FormatMessage(Win32::GetLastError);

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    to: 
    my $DsGetDcName_declare = <<'END_OF_DECLARE';
  DWORD DsGetDcName(
    LPCTSTR ComputerName,
    LPCTSTR DomainName,
    LPGUID  DomainGuid,
    LPCTSTR SiteName,
    ULONG   Flags,
    LPDOMAIN_CONTROLLER_INFO DomainControllerInfo
  );
END_OF_DECLARE

my $DsGetDcName = Win32::API->new( Netapi32 => $DsGetDcName_declare )
    or die Win32::FormatMessage(Win32::GetLastError);

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